output voltage of my phone charger is 5.6V. which type of battery suitable for my charger?? is it lithium ion??
If your phone is about 30 years old or more then it uses a lead-acid battery. If it is about 20 years old then it uses a Ni-Cad or Ni-MH battery. If it is about 10 years old then it uses a Lithium battery. Why don't you read the label on your battery??
Your phone has a complicated charger circuit inside made to charge its battery. The 5.6V adapter is simply a power supply for the charger circuit.
If you connect your 5.6V power supply directly to a battery then the battery will blow up without having the charging circuit.
I told you that the charging IC senses the charging current and when it drops to a low amount then it turns off the charger. When the charging battery voltage reaches 4.20V then IT IS NOT FULLY CHARGED! It is only about 70% fully charged.